MCP Server PROJ

A Model Context Protocol (MCP) server for coordinate system transformations and map projections.

Features

• Multiple coordinate system format support:

  • EPSG codes

  • WKT (Well-Known Text)

  • Proj string format

• Batch coordinate transformation

• Simple and intuitive API

• Dual-mode operation: server or library

Installation

pip install mcp-server-proj

Usage

Server Mode

mcp-server-proj

Library Mode

from mcp_server_proj import CoordinateTransformer

# Create transformer instance
transformer = CoordinateTransformer()

# Set source and target coordinate systems
transformer.set_source_crs("EPSG:4326")  # WGS84
transformer.set_target_crs("EPSG:3857")  # Web Mercator

# Initialize transformer
transformer.initialize_transformer()

# Transform coordinates
x, y = transformer.transform_point(116.3, 39.9)
print(f"Transformed coordinates: ({x}, {y})")

API Documentation

CoordinateTransformer

The main coordinate transformation class provides the following methods:

• set_source_crs(crs: str): Set source coordinate system

• set_target_crs(crs: str): Set target coordinate system

• initialize_transformer(): Initialize the transformer

• transform_point(x: float, y: float) -> tuple[float, float]: Transform a single point

Server

The MCP protocol server provides two tools:

• transform-coordinates: Transform coordinates between different systems

  {
    "source_crs": "EPSG:4326",
    "target_crs": "EPSG:3857",
    "coordinates": [
      {"x": 116.3, "y": 39.9}
    ]
  }

• list-supported-crs: List all supported coordinate systems

Supported Coordinate Systems

1. EPSG Codes

Standard identifiers for coordinate reference systems:

• EPSG:4326 - WGS84 Geographic

• EPSG:3857 - Web Mercator

• And many more...

2. WKT Format

Example of a geographic coordinate system:

GEOGCS["WGS 84",
  DATUM["WGS_1984",
    SPHEROID["WGS 84",6378137,298.257223563]],
  PRIMEM["Greenwich",0],
  UNIT["degree",0.0174532925199433]]

3. Proj Format

Example of WGS84:

+proj=longlat +datum=WGS84 +no_defs +type=crs

Development

Debugging

For the best debugging experience, use the MCP Inspector:

npx @modelcontextprotocol/inspector mcp-server-proj

Dependencies

• Python >= 3.12

• mcp >= 1.3.0

• pyproj >= 3.0.0

License

MIT

Author

radial-hks (radialjiajie@gmail.com)

Contributing

Issues and Pull Requests are welcome!